Piano-playing mechanism.



G. W. ATKINSON.

PIANO PLAYING MECHANISM. APPLICATION FILED 1,111.14, 1910.

1,005,793. Patnted 0011.17,]911.

W/7IVI'SSES m/ M KM/JM C/i 711 aw COLUMIIA PLANOOIAIM CE, IWAININGTON,D. C.

UNITED STATES PATENT OFFICE.

CLAUDE WILLIAM ATKINSON, OF GREAT MISSENDEN, ENGLAND.

PIANO-PLAYING MECHANISM.

To all whom it may concern:

Be it known that I, CLAUDE VVILLIAM AT- KINSON, a subject of the King ofGreat Britain and Ireland, residing at Great Missenden, in the county ofBucks, England, have invented new and useful Improvements in andRelating to Piano-Playing Mechanism and the Like, of which the followingis a specification.

This invention relates to piano playing mechanism and has reference tothe construction of a vacuum chest and the arrangement of the pneumaticoperated de vices therein, for working the valves.

The object of this invention is the provision of valve pneumaticmechanism of simple form and cheap construction.

In order that the invention may be the better understood I will nowproceed to de-- scribe the same in relation to the accompanying drawing,reference being had to the letters and figures marked thereon.

Like letters refer to like parts in the various figures in which Figure1 is a sectional elevation of a part of the vacuum chest, and thearrangement of the valves and valve operating mechanism therein. Fig. 2is a part plan of the bottom plate of the vacuum chest showing thedisposition of the depressions.

In the bottom plate a of the vacuum chamber 1) which is made of metal orother suitable material of uniform thickness I form a series ofdepressions o by stamping pressure one for each note and over eachdepression a diaphragm d of flexible material is disposed in order toform a purse to operate-the valve stem 6. I may cement the diaphragm din position upon the plate a or equivalently I may arrange a cover platef held down by screws 9 or other equivalent means in such a way as tomaintain an air tight joint between the diaphragms cl and Specificationof Letters Patent.

Application filed January 14, 1910.

Patented Oct. 17, 1911.

Serial No. 538,011.

the plate a of the vacuum chest. The cover plate f may be of such alength as to form a series of covers for several purses to affordsimplicity of fixture. A small hole It may be made in the cover plate fcoincident with the axis of each depression to serve as a guide for thevalve stem 6. Tracker pipes 71 are taken from the depressions 0 andconnected to the tracker in the usual way. A bleed hole is is providedin the diaphragm or in any other suitable position in order to effectthe relief of the internal pressure during operation in the usual way.

The valve stem 6 carries the usual valves Z which operate in theordinary manner for controlling the power pneumatics.

Having now particularly described my invention what I desire to secureby Letters Patent is In a pneuamtic piano playing mechanism, a vacuumchest having a wall formed of a plate of depressible material of uniformthickness, a plurality of stamped depressions formed integrally in saidplate, a valve stem, a flexible diaphragm disposed over each depression,restricted communicating means between the chambers on opposite sides ofthe diaphragm, an independent cover plate holding said diaphragmjointedly on said wall over each depression, means for fastening saidcover plate in position, guiding means on said cover plate for the valvestem in each valve mechanism, and connections from orifices in thetracker board to the various spaces within said depressions,substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

CLAUDE WILLIAM ATKINSON.

Witnesses:

CHAS. R. BULLOUGH, H. D. JAMEsoN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). C.

